Red Hineys in Dorrance, KS   Girls are given a piece of brown paper towel and red paint.  They are to go in the restroom, paint their butt and leave the print on the paper.  They bring it to the bartender, who then hangs it on the wall with the rest of them. 

I always thought that should be a audience participation event.  Kind of like thumbs up, you print in front of everyone, thumbs down you go to the john to print.